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Cardiovascular System
The following chapter will focus on the cardiovascular system. Pertinent questions, answers, and
rationale will be reviewed. Answers for this chapter can be found beginning on page 115.
Key Words: Heart; cardiovascular; rhythm; ventricles; atrial.
1. All of the following are true regarding the interaction between respirations and circulation except:
a. The Mueller maneuver decreases afterload.
b. The hemodynamic effects of changing intrathoracic pressure dominates over changing
intrathoracic volume.
c. Hypoxic pulmonary vasoconstriction is noted
when alveolar oxygen pressure (PaO2) drops to
less than 60 torr.
d. The single most important cardiopulmonary
interaction is the effect that ventilator induced
changes in intrathoracic pressure have on right
ventricular preload.
e. Venous return parallels transmural pressure of
the right atrium.
c. Restriction of left ventricular filling by the
stretched pericardium.
d. All of the above.
4. Which of the following statements is true pertaining to cardiopulmonary interaction?
a. The cardiopulmonary interaction is of greatest
clinical importance for the failing left ventricle.
b. In the failing heart, the effect of changes in
intrathoracic pressure on preload will dominate
over the effects on afterload.
c In young infants with less compliant ventricles
with a limited contractile reserve, positive pressure ventilation with increased intrathoracic
pressure may be detrimental.
d Afterload is best approximated by left ventricle
preload.
2. Ventricular afterload is best approximated by which
of the following?
a. Ventricular end-diastolic pressure.
b. Ventricular end-diastolic volume.
c. Systolic blood pressure.
d. Mean blood pressure.
e. Ventricular wall stress.
5. All of the following statements are true regarding
the fetal circulation except:
a. The foramen ovale allows equalization of preload of the right and left ventricles.
b The right ventricle ejects more highly oxygenated blood than the left ventricle, because it
receives the umbilical vein blood.
c. The right and left ventricular pressures are nearly equal in utero.
d The right ventricle ejects more blood than the left
ventricle owing to the difference in afterload.
3. The mechanism operative in ventricular interdependence is:
a. Right-to-left shift of the interventricular septum.
b. Constraint of left ventricular expansion by
stretch of common ventricular myofibrils.
From: Pediatric Critical Care Review
Edited by: R. A. Hasan and M. D. Pappas © Humana Press Inc., Totowa, NJ
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Pediatric Critical Care Review
6. Which of the following is true regarding the fetal
and newborn myocardium?
a. A low contractile element concentration is present in the newborn myocardium.
b. Because fetal heart functions at the peak of the
ventricular function curve, combined ventricular output is maximum at a resting atrial pressure of 3–5 mmHg.
c. Compared with the adult, the newborn heart has
higher indices of myocardial performance at
rest, but is unable to significantly improve ventricular performance.
d. Small increases in afterload decrease cardiac
output more significantly in the fetus and the
infant compared with the adult, and nitroglycerin increases cardiac output more in the adult
compared with the infant.
e. All of the above.
7. Hemodynamic changes at birth include:
a. Right ventricular afterload decreases, and left
ventricular afterload decreases.
b. Right ventricular afterload decreases, and left
ventricular afterload increases.
c. Both right ventricular and left ventricular afterload increase.
d. Right ventricular afterload increases, and left
ventricular afterload decreases.
e. None of the above.
8. Which of the following contributes the most to the
total peripheral resistance?
a. Aorta and large arteries.
b. Small arteries.
c. Arterioles.
d. Capillaries.
11. Ischemia of the myocardium with associated symptoms and signs is rarely seen with aortic regurgitation, but is commonly seen with aortic stenosis.
Which of the following underlying pathophysiological phenomena related to these clinical entities is
true?
a. Maintaining blood pressure by increasing stroke
volume rather than vasoconstriction is more O2
efficient.
b. The O2 cost of isometric contraction (pressure
work) is much greater than isotonic contraction
(volume work).
c. Increasing cardiac output by afterload reduction,
which increases stroke volume, but decreases
pressure, greatly improves the efficiency of the
heart.
d. All of the above statements are true.
12. Regarding the figure below, match the following
statement(s) with their correct answer below:
a. Area A.
b. Area B.
c. Both.
d. Neither.
____ Represent(s) myocardial O2 supply.
9. The major portion of cardiac O2 consumption is
used to support which of the following?
a. Myocardial wall tension.
b. The product of stroke volume and mean arterial
pressure.
c. Electrical activation of the myocardium.
d. None of the above.
13. Ischemic heart disease (IHD) should be sought as a
diagnosis in neonates who are critically ill. Risk
factors for IHD in neonates include:
a. Increased intracavity pressure.
b. Variable aortic pressure.
c. Ductal run-off.
d. Global hypoxia and episodes of arterial desaturation.
e. All of the above.
10. Which of the following situations is considered to
be least efficient with regard to myocardial O2 consumption and myocardial wall tension?
a. Poor myocardial compliance.
b. A heart with left ventricular hypertrophy.
c. A dilated heart with a small preload.
d. A dilated heart with a large preload and a thin
left ventricular wall.
14. Which of the following statements is true regarding
IHD in critically ill neonates?
a. IHD is almost unheard of.
b. IHD is treated with O2, positive pressure ventilation, and inotropes.
c. Symptoms resolve in 48 hours with supportive
care, whereas the electrocardiogram and radiographic changes resolve in 2 weeks.
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d. The clinical picture is that of hypoxemia, cardiomegaly, cardiogenic shock, and tricuspid insufficiency.
e. All except A are true.
15. Clinical situations in which myocardial ischemia
and infarction are recognized in children with congenital heart disease include:
a. Right ventricular infarction in total anomalous
pulmonary venous drainage.
b. Left ventricular infarction in aortic stenosis.
c. Biventricular infarction in transposition of the
great arteries.
d. All of the above.
e. None of the above.
16. Which of the following is a true statement concerning anomalous left coronary artery?
a. By 4 months of age, the majority of infants will
have developed a coronary fistula.
b. Without treatment, 80% of infants will survive
to adulthood.
c. There is frequently a history of cyanosis at birth.
d. The clinical condition may mimic gastroschisis.
e. All of the above.
17. The leading cause of IHD in children is:
a. Kawasaki syndrome.
b. Left anomalous coronary artery.
c. Severe aortic stenosis.
d. Atherosclerotic disease.
e. None of the above.
18. Coronary artery involvement and cardiac abnormalities are more common in children with
Kawasaki syndrome who exhibit which of the following characteristics?
a. Are female older than 8 years of age.
b. Have associated torus fracture.
c. Have had a fever less than 2 days.
d. Have an erythrocyte sedimentation rate of less
than 20 mm/hour.
e. None of the above.
19. A 13-year-old male victim of a motor vehicle accident with multiple trauma and closed head injury is
in the pediatric intensive care unit (PICU) with elevated intracranial pressure. Poor peripheral perfusion and low urine output is noted with a central
venous pressure of 18 mmHg. True statements pertaining to this patient include:
a. Impaired left and right ventricular function has
been reported in patients with closed head injury.
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b. Head injury causes an enhanced autonomic
response with direct sympathetic cardiac stimulation and an enhanced level of circulating catecholamines.
c. ST-T changes on the electrocardiogram are seen
in head injury patients.
d. Myocardial injury is seen frequently in the setting of thoracic trauma.
e. All of the above.
20. During high permeability pulmonary edema:
a. The ratio of extravascular lung water to dry lung
weight is decreased.
b. The blood-free dry weight of the lung is
increased.
c. The dry weight of the lung is decreased.
d. None of the above is true.
21. Which of the following statements pertaining to
this equation is true?
Q = Kf (Pc-Pi) – σ ( Πc – Πi )
a. Kf is the reflection coefficient.
b. σ is the filtration coefficient.
c. When σ = 1, there is no restriction to passage of
protein across the capillary membrane.
d. When σ = 0 there is absolute restriction to the
passage of protein across the capillary membrane.
e. None of the above.
22. Of the various causes of heart failure that produce
pulmonary edema not related to congenital heart
disease, anthracycline cardiotoxicity is an important type. A factor that potentiates the incidence of
heart failure because of anthracycline is:
a. Administration of bleomycin.
b. Administration of cyclophosphamide.
c. Mediastinal radiotherapy.
d. All of the above.
e. None of the above.
23. A 13-year-old boy with a previous history of acute
lymphoblastic leukemia treated with chemotherapy
including doxorubicin presents to the PICU in
florid pulmonary edema. The chest radiograph
shows an enlarged heart with evidence of alveolar
edema. All of the following statements are true of
this clinical scenario except:
a. Symptoms of congestive cardiac failure caused
by doxorubicin toxicity may appear years after
the last dose of doxorubicin.
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b. The mortality rate for this patient is at least
50–60%.
c. Cardiotoxicity as a result of doxorubicin is dose
independent.
d. Cardiac enzyme assay and serial chest radiographs have not been useful in the prediction
of cardiomyopathy.
e. Because anthracyclin cardiomyopathy may be
reversible in children, intensive cardiac support
with tracheal intubation and positive pressure
ventilation may be warranted to treat an acute
episode of pulmonary edema.
24. Which of the following is not a cause of high permeability pulmonary edema?
a. Salicylate intoxication.
b. Prolonged exposure to high fraction of inspired
oxygen (FiO2).
c. Anaphylaxis associated with pulmonary edema.
d. A combination of doxorubicin and cyclophosphamide.
e. Heroin overdose.
25. Which of the following organ systems is most frequently affected by heroin overdose?
a. Kidney.
d. Lung.
b. Heart.
e. Skeletal muscle.
c. Brain.
26. Which of the following statements describing pulmonary vascular tree physiology is true?
a. Normal matching of ventilation to perfusion is
achieved by local hypoxic pulmonary vasoconstriction.
b. Hypoxic pulmonary vasoconstriction is usually
localized and reversible.
c. In neonates, hypoxic pulmonary vasoconstriction may persist even after the hypoxia has been
corrected.
d. Potential anatomic shunts that are present inside
the lungs can open up and may account for the
cyanosis noted during conditions of elevated
pulmonary pressure.
e. All of the above.
27. Which of the following physiological changes in
response to hypoxia is not likely?
a. Impairment of short term memory occurs at
approximately PaO2 of 60 torr.
b. When the PaO2 falls to less than 60 torr, carotid
and aortic bodies are activated leading to tachycardia and hyperventilation.
c. Levels of 2,3 diphosphoglycerate increase in 20
minutes.
d. Tubular reabsorption of Na+ is impaired at a low
PaO2.
e. PaO2 of less than 40 torr produces twitching and
seizures.
28. A two and a half-month-old baby with Tetralogy of
Fallot is brought to the emergency department and
subsequently to the PICU for progressively turning
blue soon after waking when his mother began to
feed him. He became fussy, began to cry, and since
then, has been getting progressively more cyanotic
and limp. All of the following are true statements
except:
a. The onset of these symptoms in early morning
and with feeding is characteristic.
b. The peak incidence is seen at this age.
c. There is a strong negative correlation between
PaO2 and the incidence of attacks.
d. Squatting or knee–chest position redistributes
systemic blood flow to the upper body to
improve pulmonary blood flow, but does not
affect arterial oxygen saturation.
e. Propranolol can abort the attack and may
decrease the frequency of these episodes when
used chronically.
29. Cyanosis at a normal PaO2 occurs in:
a. A victim of smoke inhalation.
b. A child overdosed on shoe dye.
c. A patient with a hematocrit of 75%.
d. All of the above.
30. In the postoperative period, a right-to-left shunt
helps preserve cardiac output and decreases postoperative complications in children with which of the
following conditions?
a. Repair of Tetralogy of Fallot.
b. Repair of truncus arteriosis.
c. Fenestrated modified Fontan procedure.
d. All of the above.
e. None of the above.
31. A 6-month-old child with Down’s syndrome who
underwent repair of an atrioventricular canal defect
was admitted to the PICU 6 hours ago. High pulmonary artery pressure is noted along with a
decreased O2 saturation to the 80s and evidence of
low cardiac output. The first priority after stabilization of the patient is:
a. Adjust the vent settings.
b. Increase FiO2.
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c. Obtain a chest radiograph.
d. Obtain an echocardiogram to rule out any residual abnormality.
e. None of the above.
32. All of the following statements are true regarding
pulmonary circulation in this patient except:
a. O2 is a very strong pulmonary vasodilator after
cardiopulmonary bypass.
b. The effect of hyperventilation on pulmonary
vascular resistance is mediated by changes in
pH rather than PCO2.
c. Pulmonary vascular resistance increases with
increasing postoperative hematocrit.
d. Pulmonary vascular resistance increases in the
postoperative night as pulmonary artery pressure is maintained or increases, thus cardiac
output decreases.
e. Pulmonary vascular endothelial dysfunction
after cardiopulmonary bypass is common.
33. A 5-day-old who presented with rapid onset of
shock a few hours ago is found to have hypoplastic
left heart syndrome and is on a prostaglandin-E2
infusion. The patient is being mechanically ventilated. You notice that the O2 saturation on pulse
oximetry is 92%. You anticipate all of the following
except:
a. Pulmonary congestion.
b. Right ventricle may suffer from diastolic overload.
c. Use of hyperventilation and tolazoline will
improve saturation and the patient’s overall
condition.
d. Pulmonary blood flow is increased.
34. All of the following are true regarding chylothorax
except:
a. Malnutrition is a recognized complication.
b. Most frequently seen with intrapericardial procedures.
c. May occur without damage to the thoracic duct.
d. Pleural fluid may appear serosanguinous and
will not clot.
e. Pleural effusion may develop as late as 1 month
after surgery.
35. Regarding treatment of chylothorax:
a. Pleural drainage is required to improve ventilation and prevent atelectasis.
b. To decrease lymph flow, a high-carbohydrate,
high-protein, medium-chain triglyceride diet
with reduced fat is recommended.
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c. Malnutrition is an important complication.
d. All of the above.
36. Which of the following is an indication for surgical
ligation of the thoracic duct for chylothorax?
a. Average daily chyle loss of greater than 100
mL/year of the patient’s age, after 5 days of
medical therapy.
b. A flow of chyle that does not diminish after 2
weeks.
c. Nutritional complications that are severe.
d. All of the above.
37. Match the selections listed below with their appropriate descriptions.
a.
b.
c.
d.
The modified Fontan procedure.
Stage I Norwood procedure.
Both.
Neither.
____ Increased pulmonary vascular resistance
results in hypoxemia.
____ Increased pulmonary vascular resistance
results in cardiogenic shock.
____ Improve(s) systemic oxygenation and
reduces the obligatory diastolic overload.
38. Which of the following statements is not true
regarding fenestrated Fontan procedure?
a. Maintains the systemic perfusion when pulmonary vascular resistance is elevated.
b. Decreases the incidence of pleural effusion.
c. Increases the mortality rate in patients undergoing the procedure.
d. Can be closed in the cardiac catheterization laboratory later during hospitalization.
39. When an infant with transposition of the great arteries and an intact ventricular septum presents for
repair at 3 months of age, the best approach is:
a. Senning procedure.
b. Mustard procedure.
c. Immediate correction by arterial switch.
d. Pulmonary artery banding and a Blalock-Taussig shunt.
e. None of the above.
40. The two issues of paramount importance after arterial switch are:
a. Mustard vs Senning’s procedures.
b. Presence of atrial septal defect and patent ductus arteriosus.
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c. Global performance of left ventricle and focal
myocardial ischemia.
e. None of the above.
41. Chylothorax is least likely to occur with repair of:
a. Aortic or pulmonary valve surgery or ventricular septal defect.
b. Patent ductus arteriosus ligation.
c. Repair of coarctation.
d. Glenn anastomosis.
e. Shunt procedure (Blalock-Taussig, Waterston,
Pott).
42. Postoperatively, patients with transposition of the
great arteries undergoing arterial switch are characterized by all of the following except:
a. Unrecognized left-to-right shunts or overzealous volume administration that can precipitate
sudden hemodynamic compromise.
b. Focal ischemia is a recognized complication.
c. Compromised cardiac output responds favorably to afterload reduction.
d. Global left ventricular systolic dysfunction is
not seen.
e. The left ventricle is typically dilated and tolerates any further load poorly.
43. Following a Blalock-Taussig shunt, true statements
include all of the following except:
a. The ipsilateral arm may be cold and pulseless
for 48–72 hours.
b. Blalock-Taussig shunt is generally performed
on the side opposite the aortic arch.
c. Ipsilateral pulmonary edema is a recognized
complication.
d. Flow is determined by the size of the subclavian
artery; size of the graft itself is not critical.
e. Diuretics should be avoided if possible.
44. Which of the following statements is inaccurate
regarding cardiac transplantation?
a. A major cause of early postoperative failure is
right ventricular failure from increased pulmonary vascular resistance.
b. Matching is based on ABO compatibility.
c. Systemic hypertension is frequently seen postoperatively caused by cyclosporin-A.
d. Endomyocardial biopsy is the best way to diagnose rejection when done weekly postoperatively.
e. Ketamine will enhance myocardial function.
45. A 5-month-old underwent repair of Tetralogy of
Fallot through a ventriculotomy with a transannular
patch. Central venous pressure is 10 mmHg. Poor
perfusion of the extremities is noted with low urine
output. A bolus of colloid 15 mL/kg is given over
20 minutes. It is noted that the central venous pressure has decreased to 7 mmHg. This suggests that:
a. Ventricular compliance has improved.
b. Afterload has decreased following volume
expansion.
c. Myocardial perfusion has improved.
d. This clinical scenario is not possible.
e. A, B, and C.
46. A 12-year-old is admitted to the PICU with septic
shock. A pulmonary artery catheter is inserted for
hemodynamic monitoring. Left ventricular stroke
work index was 30 g/minute/m2 4 hours ago. Now
left ventricular stroke work index is 55 g/minute/m2.
This indicates that:
a. Afterload has increased.
b. Afterload has decreased.
c. Contractility has improved.
d. None of the above.
47. The compensatory state of shock is least likely
with:
a. Cardiogenic shock.
b. Septic shock.
c. Hypovolemic shock.
d. Obstructive shock.
48. Match the selections listed below with their appropriate descriptions.
a. An adolescent with extensive orthopedic injury receiving positive mechanical ventilation.
b. An infant with critical aortic stenosis
receiving positive pressure ventilation.
c. Both.
d. Neither.
____ With inspiration, there is a decrease in pulse
pressure without a phase lag and diastolic
pressure falls.
____ With inspiration, there is an increase in
pulse pressure without a phase lag and diastolic pressure increases.
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49. A mechanism responsible for pulmonary edema
associated with upper airway obstruction does not
include which of the following?
a. Increased right ventricular afterload.
b. Ventricular interdependence.
c. Increased left ventricular afterload.
d. Decreased left ventricular afterload.
50. An infant with congestive cardiac failure is admitted to the PICU. Intermittent “grunting” is noted.
All of the following are true statements regarding
this clinical scenario except:
a. Grunting is a form of the Valsalva maneuver.
b. Grunting decreases left ventricular afterload.
c. Grunting is a form of the Mueller maneuver.
d. A decrease in left ventricular preload may shift
the Starling curve to a more favorable position,
thus decreasing myocardial O2 consumption.
e. This patient is likely to benefit from inotropic
drugs.
51. Nitroprusside would be least effective for:
a. Congestive heart failure as a result of cardiomyopathy.
b. Mitral regurgitation.
c. Ventricular septal defect with congestive cardiac failure because of significant left-to-right
shunt.
d. Myocardial dysfunction following cardiopulmonary bypass.
e. Hypotensive anesthesia.
52. Which of the following statements is least accurate
regarding the toxicity of nitroprusside?
a. Neuroexcitatory symptoms of delirium, confusion, and convulsions are a result of thiocyanate
accumulation.
b. Thiocyanate tends to accumulate in patients
with renal dysfunction.
c. Thiocyanate is not removed by either hemo or
peritoneal dialysis.
d. Measurement of thiocyanate concentration does
not have relevance to detecting cyanide toxicity.
e. Methemoglobin levels should be determined
during prolonged infusion of nitroprusside.
53. Match the selections listed below with their appropriate descriptions.
a. Nitroprusside.
b. Nitroglycerin.
c. Both.
d. Neither.
____ The preferred drug when treating a child
with congestive cardiac failure, pulmonary
edema, and marginal blood pressure.
____ The preferred drug for the treatment of congestive cardiac failure induced by mitral or
aortic regurgitation.
____ The preferred drug for congestive cardiac
failure with preserved blood pressure,
because it produces a greater increase in cardiac output in this setting.
54. Which of the following is true regarding volume
resuscitation in shock state?
a. Isotonic solutions may be administered safely
up to an amount equivalent to 200% of the
patient’s circulating blood volume.
b. Hetastarch and Dextran administration should
not exceed 200 mL/kg/dose because of concerns about hemostasis.
c. Rapid fluid resuscitation in excess of 40 mL/kg
in the first hour of evaluation is associated with
improved survival and no increased risk of pulmonary edema in patients with septic shock.
d. Plasma catecholamines increase only marginally in shock states.
e. None of the above.
55. In the United States, trauma is the leading cause of
death in children older than 1 year. The major contributor to mortality is:
a. Hypovolemic shock. d. Head injury.
b. Cardiogenic shock.
e. Infection.
c. Septic shock.
56. In the PICU, the major cause of cardiogenic shock is:
a. Myocarditis.
b. Kawasaki syndrome.
c. Anomalous left coronary artery.
d. Postoperative repair of congenital cardiac
lesions.
e. Isoproterenol treated asthmatics.
57. Impaired cellular metabolism occurs earliest during
the clinical course of which type of shock?
a. Cardiogenic shock.
b. Septic shock.
c. Hypovolemic shock.
d. Obstructive shock.
e. Anaphylactic shock.
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58. In a child who presents with a temperature of 42°C,
poor peripheral circulatory status, altered mental
status, and acidosis:
a. Heat shock protein is released in excessive
amounts.
b. Anhydrosis results from cellular sweat gland
damage.
c. Disseminated intravascular coagulation is a recognized complication.
d. Riley-Day syndrome is a possibility.
e. All of the above.
59. A 14-year-old who sustained a fractured femur suddenly develops chest pain and dyspnea. Pathophysiological changes likely leading to this clinical
picture include:
a. Sudden right ventricular failure leading to
shock.
b. Pulmonary vasoconstriction and pulmonary
capillary endothelial damage.
c. Massive release of vasoactive mediators from
pulmonary circulation leading to circulatory
failure.
d. All of the above.
60. Useful diagnostic work-ups include:
a. Microscopic urinalysis.
b. Ventilation–perfusion scan.
c. Pulmonary angiography.
d. All of the above.
61. Therapy for the patient referenced in Question 60
would include all except:
a. Optimizing hemodynamics.
b. Optimizing oxygenation.
c. Prevention of further episodes.
d. Removal of emboli.
62. Air embolism with fatal cerebral complications
occurs with:
a. Laceration of a large vessel following trauma.
b. Spinal surgery.
c. Cranial surgery.
A. All of the above.
Questions 63–65: A 12-year-old child who has had
renal transplantation presents with sudden onset of
acute, severe abdominal pain with prostration. He has
been receiving azathioprine and prednisone for the last
4 months. He is hypotensive, poorly perfused, and pale
with marked abdominal rigidity. No hematemesis or
melena are noted. Urinalysis is unremarkable. Amylase
and lipase are 850 and 500 IU/dL, respectively.
Pediatric Critical Care Review
63. The most likely diagnosis is:
a. Pyelonephritis.
b. Chronic rejection.
c. Pancreatic shock.
d. Perforated duodenal ulcer preceded by hemorrhage.
e. None of the above.
64. Anticipated complications in this patient include:
a. Hypercalcemia.
b. Hyperuricemia.
c. Acute respiratory distress syndrome.
d. Hypervolemia.
e. Appendicitis.
65. Appropriate interventions in the patient would
include which of the following?
a. Volume restriction.
b. Appropriate management of hypercalcemia.
c. Surgical exploration.
d. Appropriate management of respiratory dysfunction.
66. When managing children at risk of developing
shock states, all of the following are true except:
a. Urine output in children is normally 2–3 mL/
kg/hour.
b. It is usual for oliguria to occur before the alterations in blood pressure or the development of
significant tachycardia.
c. Central filling pressure always reflects intravascular volume accurately.
d. Intravascular volume expansion by as much as
30% may not significantly alter right atrial pressure .
e. The major determinants of cardiac filling pressure are ventricular function and compliance.
67. A 3-year-old with a 2-day history of frequent
episodes of diarrhea is admitted to the PICU with a
diagnosis of hypovolemic shock. There is no evidence of systemic infection and chest radiograph
shows a normal size heart and normal lung fields.
Which of the following statements regarding management of this patient is least accurate?
a. It is unlikely that monitoring of central venous
pressure adds significantly to careful, repeated
physical exams and monitoring of urine output.
b. Every attempt should be made to elevate the
central venous pressure to greater than 14 mmHg.
c. The concept that central filling pressure always
reflects intravascular volume accurately is misleading.
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d. If this patient develops oliguria or anuria, central venous pressure monitoring becomes essential to avoid fluid overload.
68. Regarding metabolic acidosis in the shock state, all
of the following are true except:
a. Base deficits greater than 10 mEq/L in cardiogenic and septic shock are associated with a
worse outcome than a similar situation in hypovolemic shock.
b. Hepatic conversion of lactate or acetate to correct acidosis is impaired in most shock states.
c. Severe metabolic acidosis associated with
organic acidemia can be treated with peritoneal
dialysis.
d. With correction of acidosis, serious hypercalcemia and hyperkalemia may occur.
69. Which of the following is true of hemodynamic
management of shock states?
a. When volume resuscitation greater than 50–70
mL/kg is administered in the first 4–6 hours,
invasive monitoring should be considered.
b. In patients with acute respiratory distress syndrome, central filling pressures should be maintained at a lower level (≤10 mmHg).
c. In patients with increased intracranial pressure,
inotropic support may be warranted before preload is fully augmented.
d. Application of pneumatic antishock garments in
the field does not alter survival.
e. All of the above.
70. The functional reserve of the cardiovascular system
in the infant is limited owing to:
a. Abundance of contractile elements in the
neonatal myocardium.
b. Sarcoplasmic reticulum is more abundant.
c. Less compliant myocardium leading to increased
myocardial wall stress.
d. Pulmonary vascular bed is minimally recruited
under basal conditions.
71. The Bezold-Jarisch Reflex refers to:
a. Under basal conditions, sympathetic tone to the
heart is relatively low, whereas parasympathetic
tone is dominant.
b. Stretching of the carotid sinus triggers a
parasympathetic-efferent activity resulting in
bradycardia and vasodilation.
c. Hypovolemia with a decreased stretching of
aortic arch baroreceptors causes a sympathetic
output with tachycardia and vasoconstriction.
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d. Activation of cardiopulmonary baroreceptors
localized in the atrial and ventricular wall result
in vagal stimulation with bradycardia and
vasodilation.
e. None of the above.
72. Risk factors for infection following radial artery
cannulation include:
a. Insertion by surgical cut down.
b. Inflammation at the insertion site.
c. Cannulation for more than 4 days.
d. All of the above.
73. The most serious complication of axillary artery
cannulation is:
a. Thrombosis.
b. Distal ischemia.
c. Embolism.
d. Brachial plexus injury.
e. Infection.
74. Precautions to be taken during pulmonary artery
catheter insertion include all of the following
except:
a. When withdrawing the catheter, always deflate
the balloon by disconnecting the syringe and
opening the valve to the atmosphere.
b. Dysrhythmias occur most commonly during
insertion into the right atrium, probably because
of irritation of the arterioventricular mode.
c. The catheter should not be advanced more than
10 cm without seeing a change in waveform
after entering the right atrium.
d. Balloon rupture is more commonly seen in
pediatric patients.
e. Risk of infection is reduced if the catheter is left
in place for less than 3 days.
75. The figure below shows various curves that represent cardiac output as measured by the thermodilution technique. Which of the following statements
is most accurate?
a. Curve “A” represents a patient with a ventricular septal defect.
b. Curve “C” is likely to give a falsely high cardiac
output.
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c. Cardiac output obtained by Curve “B” will be
higher than Curve “A”.
d. Curve “A” will correspond to a higher cardiac
output than Curve “B”.
e. All of the above.
Questions 76–79: Please reference the figure below.
Loop A–B–C–D is the normal pressure volume loop of
the cardiac cycle.
c. Point A.
d. Point E.
e. Point D.
77. An intervention is performed which results in loop
A–B1–C1–D. The most likely explanation for this
change is:
a. A bolus of intravenous fluid.
b. An increase in afterload.
c. An increase in contractility.
d. All of the above.
78. Provided there is no change in pressure, loop
A1–B–C–D1 is most likely a result of:
a. Increased preload.
b. Increased contractility.
c. Decreased contractility.
d. None of the above.
76. In the normal loop (A–B–C–D), the point at which
the aortic valve opens is:
a. Point B.
b. Point C.
79. Provided the contractility is unchanged, loop
A2–B–C2–D2 is most likely a result of:
a. Increased end-diastolic pressure.
b. Increased afterload.
c. Increased contractility.
d. Decreased afterload.
e. None of the above.
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